The present invention relates to byproducts of recycled paper and, in particular, to a molded stock formed from one or more relatively dry, colorized batches of admixture ingredient. Each batch ingredient includes a soybean derived adhesive binder, a separate colorant and other additives. Predetermined concentrations of the batch ingredients are combined and cured under pressure in the presence of microwave, radio frequency or thermal energy.
With growing concerns and pressures to find alternative uses for waste matter, various efforts have been directed to developing conversion processes for deriving usable products from recycled newsprint and other paper stocks. The majority of these efforts have been directed to producing building insulation materials in shredded form and in molded sheet form. Such sheet goods can comprise recycled paper or relatively more dense or thicker materials such as construction grade panel board or liana board. These processes may include the addition of various adhesives and additives, molding and curing steps.
Processes directed to the production of insulation materials can be found upon directing attention to U.S. Pat. Nos. 4,184,311 and 4,300,322. The former patent discloses a molded insulation product laminated to an outer covering. The latter discloses a dry shredded mixture which is injected into a batting envelope and which envelope can be mounted in conventional fashion. Sprayed processes also exist in which shredded newsprint particulate is mixed with water and sprayed into structural spaces, where the material hardens, after skimming away excess material. Australian application Serial No. 36603/84 entitled Improved Insulation Product also discloses a molded newsprint insulation. The material is principally air cured, although reference is made to microwave curing.
U.S. Pat. No. 4,148,952 discloses a process for partially shredding and consolidating waste paper to facilitate transport. U.S. Pat. Nos. 4,111,730 and 5,011,741, otherwise, disclose processes wherein a binder derived from a cooked starch and urea formaldehyde resin are added to slurries which are molded under pressure and cured to form uncolored board stocks. The former may also be used as a structural building member.
U.S. Pat. Nos. 4,994,148 and 5,064,504 also disclose methods for creating molded structural blocks from a newsprint slurry which is formed in a screen wall molding chamber. A plaster or cement binder is also disclosed. Curing of the blocks is effected through air drying.
various adhesive preparations, including soybean derived adhesives, for a broad range of laminate gluing applications are also disclosed in the Handbook of Adhesives, Van Nostrand Rheinhold (1962).
Finished materials produced by the prior art, unless separately laminated with a decorative finish laminate, have uniformly demonstrated undesirable dull grey or matte grey colors without any distinctive or aesthetically appealing pattern.
Unknown in the prior art is a process utilizing unprocessed waste papers to form decorative, structurally stable building stocks having a natural stone appearance and which stocks can be molded or extruded as sheet goods or in a variety of shaped forms. Natural stone appearing stock requiring specific bulk color patterns and/or esthetically pleasing surface textures are especially unknown for use as finished surface treatments, such as for floors, walls, ceilings and furniture.
The lack of such a construction stocks is believed due to a variety of factors, including: (1) shredding and re-pulping of waste paper reduces the length of the cellulose fibers and thereby compromises the tear and shear strength of the finished material; (2) the prior lack of means for repeatedly producing an aesthetically pleasing texture and coloration of the finished material; (3) costly de-inking and bleaching of the pulp stock which reduces the competitiveness of the material; and (4) the potential presence of unknown and undesired contaminates in the raw waste paper stock that can deleteriously effect surface finish and structural integrity of the produced stock.
Otherwise, it has been found that irregularly patterned, multi-colored materials such as the mineral aggregates and, for example, granite, are not easily duplicated or replicated in modern composites or laminates. These difficulties have been resolved through an appreciation of the process of forming natural stone and the relationship of human perceptions of natural stone.
That is, natural stone is formed from densely packed random crystals of variously colored minerals which, over time, in response to specific physical laws combine toward a minimum energy system. Such a process parallels recent understandings of the theories of ordered chaotic systems pioneered by F. Mandelbrot. Human eye-brain perceptions in contrast are learned and thus any recognition and appreciation that a material is "natural" or "artificial" is formed upon a mental comparison in relation to learned perceptions made by each observer. Because the artificially produced materials of the invention closely approximate the natural random ordering of stone, particularly granite, the resultant material is perceived to be granite.